The complimentary close in an official letter is:AYours truelyBYours sincerelyCYours faithfullyDYours respectfullyAnswer: C. Yours faithfully Read Explanation: Complimentary Close Demi official letters are concluded by Yours Sincerely. The complimentary close in an official letter is Yours faithfully . The complimentary close of a business letter is Yours faithfully or Yours truely Read more in App